As well known in the art, a cooking oven is a cooking instrument for receiving and cooking food by a radiant heat and a convection heat within a cavity of the oven.
As the oven is diversified in its function, even kind of cookable food increases, so its use increases. Therefore, an opportunity of contaminating the internal of the cavity owing to food dregs, etc. increases that much. In order to clean the stained cavity, the oven generally has a self-cleaning function.
The self-cleaning function refers to a function of cleanly cleaning the cavity internal by keeping the cavity internal of the cooking oven at about 450° C. for a predetermined time (about 15 minutes to the minimum), thermally analyzing food contaminants accumulated in the internal, and then exhausting out gas and smoke generated from the thermal analysis. The self-cleaning function requires processes of increasing a temperature of the cavity internal to a high temperature of about 400° C., maintaining the high-temperature cavity internal for about 15 minutes, and then again cooling the cavity internal. In general, it takes two hours or more to complete all the processes.
During the operation processes, the cavity is kept at a high temperature. Thus, a careless infant or user may get burned because of a heat emitted out when a door is opened. In order to prevent this accident, the oven door is now equipped with a safety device. However, because the safety device is generally installed at the outside of the door, the user may undesirably open the door by force, thus reducing by half a function of a lock device and also having poor appearance.